A fuel cell system includes a fuel cell that generates electricity by an electrochemical reaction between fuel gas and oxidation gas (reaction gases), a gas supply flow path for supplying the reaction gases to the fuel cell, and a gas discharge flow path for discharging the reaction gases from the fuel cell. In addition, a open/close valves for a fuel cell equivalent to the fluid control valves can be installed in such a gas supply flow path and a gas discharge flow path.
For example, in a case of an open/close valve for the fuel cell disclosed in JP 2004-183713 A, a valve member having a pillar section is provided in order to block and connect flow in a gas flow path by displacing the pillar section along the axis direction. The inside of this open/close valve for the fuel cell is divided into two chambers by a diaphragm. This valve is provided in a hydrogen discharge unit for discharging hydrogen to be discharged from the fuel cell, and one chamber of the two chambers of the valve is connected to a path which is branched from an air supply path for supplying the air to the fuel cell. The other chamber of the two chambers has a coil spring, and the coil spring urges the valve member to open the other chamber and discharge hydrogen gas to be discharged. When the one chamber is supplied with air upon use, pressure acts on the diaphragm to cause the valve member to be seated on a valve seat against the resilience of the coil spring, thereby closing the other chamber.
Further, in the case of the fuel cell hydrogen regulator valve disclosed in JP 2004-150090 A, the inside of the housing is divided into three chambers by two diaphragms connected to the valve member, to thereby make the opening of the valve adjustable according to the air pressure supplied and introduced into a regulator chamber of the three chambers, the pressure from the spring, and the pressure from hydrogen gas.
In the case of the valve for a fuel cell disclosed in JP 2004-183713 A, a flow path for discharging hydrogen to be discharged is closed by supplying the air into one of two chambers. In other words, the flow path is blocked by the pressure difference between the two chambers. Further, when opening the valve, only the pressure difference between the two chambers and the resilience of the spring are used to drive the valve to connect the flow paths. As such, there is demand for improving the responsiveness of the driven valve.
For example, when this valve for a fuel cell is used in an environment in which moisture is present, moisture adhering to the valve member portion may freeze when the valve is closed, possibly making it necessary to apply a large force to open the valve. In contrast to this, when the flows of gas in the flow path is blocked or connected using only the force of the pressure differential between the two chambers and the resilience of the spring, the valve driving force may be reduced. As such, a configuration in which the response of the valve when it is driven in response to input of signals for driving the valve is improved has been desired.
Further, in the fuel cell valve disclosed in JP 2005 150090 A, three chambers are provided. Because the center chamber is an atmospheric pressure chamber, and because positive pressure acts on the two chambers on both sides, the force for driving the valve member generated by introducing the supplied air pressure into a regulator chamber of the two chambers and the force for driving the valve member generated by the pressure from hydrogen gas present in, of the two chambers, one chamber for discharging hydrogen to be discharged, act in the opposite directions to each other. As such, there is a demand for improving the response of the driven valve.
A purpose of the present invention is to improve the response of the valve when it is driven in the fluid control valve and in the fuel cell system.